602 



Adeney — Dissolved Gases and Fermentative Changes. 



Ill experiment 2a the nitrous and. nitric nitrogen together practically equalled 

 the ammoniacal nitrogen lost, but this time, however, a very small volume of 

 carbon dioxide was formed. The volume of oxygen theoretically equivalent to 

 the nitrous and nitric nitrogen formed is 7'70 c.cs., a volume also slightly in excess 

 of that actually consumed, viz. 7*24: c.cs. 



It is interesting to note that the fermentation during these two experiments 

 was practically a nitrous fermentation, but that when the solution remaining 

 after the conclusion of the second experiment, was kept in a bottle only partially 

 filled for a single day, the nitrous acid was almost completely fermented to nitric 

 acid. 



During fermentation in experiment 3«, the nitrous and nitric nitrogen formed, 

 amounting to 0-00355 grammes, was considerably in excess of the ammoniacal 

 nitrogen lost, and a decided quantity, viz. 3-56 c.cs., of carbon dioxide was 

 produced. Nevertheless the oxygen theoretically equivalent to the total nitrous 

 and nitric nitrogen, viz. 8-81 c.cs., is decidedly in excess of that actually consumed, 

 7-2 c.cs. 



On summing together the differences from each experiment, it will be seen 

 that, by the time of the conclusion of the experiment 3a, nearly all the fermentable 

 matters, i.e. both peat and ammonia, originally present in solution PA/10, must 

 have been fermented, thus ; — 



16-59 c.cs., CO2 are equivalent to 0-00896 grms. The organic carbon originally 

 present in the solution PA/10 was 0-0089 grms. The exact coincidence between 

 these numbers is probably accidental. Again, the total nitrous and nitric nitrogen 

 amounts, it will be observed, to 0-01095, while the total organic and inorganic 

 nitrogen present in the solution when the experiments were commenced was 

 0-0107 grammes. 



The volume of oxygen theoretically equivalent to the nitrous and nitric 

 nitrogen, assuming that both were derived from the ammoniacal nitrogen, is equal 

 to 27-66 c.cs., which is very much larger than that found by analysis to have been 

 consumed. We may draw the conclusion, then, that the oxygen of the peat itself 

 must have taken part in the fermentative changes. 



It is of course, impossible to distinguish any very definite relationship between 

 the figures just considered, owing to the fact that the errors attending them are 

 too appreciable. I merely put them forward here to indicate, which we may 



